sd-bus: sync kdbus.h (ABI break)

After some reconsideration, we decided to move the binary protocol
back to 64-bit wide UIDs and GIDs. After all, it should be possible
to redefine [gu]id_t to uint64_t and things should continue to
work. As we want to avoid such data types in kdbus.h, let's move
back to 64-bit values and be safe.

In sd-bus, we have to do a translation between uint64_t and gid_t
now for supplementary gids.

Some inline comments have also been updated in kdbus upstream.

1 files changed, 17 insertions, 12 deletions

diff --git a/src/libsystemd/sd-bus/kdbus.h b/src/libsystemd/sd-bus/kdbus.h
index 6cbd01c503..fc1d77dd7c 100644
--- a/src/libsystemd/sd-bus/kdbus.h
+++ b/src/libsystemd/sd-bus/kdbus.h
@@ -70,14 +70,14 @@ struct kdbus_notify_name_change {
  *   KDBUS_ITEM_CREDS
  */
 struct kdbus_creds {
-	__u32 uid;
-	__u32 euid;
-	__u32 suid;
-	__u32 fsuid;
-	__u32 gid;
-	__u32 egid;
-	__u32 sgid;
-	__u32 fsgid;
+	__u64 uid;
+	__u64 euid;
+	__u64 suid;
+	__u64 fsuid;
+	__u64 gid;
+	__u64 egid;
+	__u64 sgid;
+	__u64 fsgid;
 } __attribute__((__aligned__(8)));
 
 /**
@@ -463,8 +463,10 @@ struct kdbus_item {
  *				cookie identifies the message and the
  *				respective reply carries the cookie
  *				in cookie_reply
- * @KDBUS_MSG_NO_AUTO_START:	Do not start a service, if the addressed
- *				name is not currently active
+ * @KDBUS_MSG_NO_AUTO_START:	Do not start a service if the addressed
+ *				name is not currently active. This flag is
+ *				not looked at by the kernel but only
+ *				serves as hint for userspace implementations.
  * @KDBUS_MSG_SIGNAL:		Treat this message as signal
  */
 enum kdbus_msg_flags {
@@ -497,9 +499,12 @@ enum kdbus_payload_type {
  * @cookie:		Userspace-supplied cookie, for the connection
  *			to identify its messages
  * @timeout_ns:		The time to wait for a message reply from the peer.
- *			If there is no reply, a kernel-generated message
+ *			If there is no reply, and the send command is
+ *			executed asynchronously, a kernel-generated message
  *			with an attached KDBUS_ITEM_REPLY_TIMEOUT item
- *			is sent to @src_id. The timeout is expected in
+ *			is sent to @src_id. For synchronously executed send
+ *			command, the value denotes the maximum time the call
+ *			blocks to wait for a reply. The timeout is expected in
  *			nanoseconds and as absolute CLOCK_MONOTONIC value.
  * @cookie_reply:	A reply to the requesting message with the same
  *			cookie. The requesting connection can match its